Retrofitting an RDC (Tyre Pressure Control) sensor is the process of adding the factory-standard Tire Pressure Monitoring System to a BMW Motorrad bike that was not originally equipped with it. Unlike basic software upgrades, this requires both the installation of new hardware and specific electronic coding to integrate the system with the motorcycle's onboard computer. 

What is RDC?

RDC uses wireless sensors mounted inside each wheel to continuously monitor and report real-time tire pressure and temperature to the rider via the instrument cluster. It provides both yellow "info" lights for minor deviations and a red warning light for a more significant pressure drop, enhancing rider safety. 

The retrofit process

Retrofitting an RDC system is a complex procedure best performed by a qualified BMW Motorrad dealer or specialist. The steps involve hardware installation, electronic wiring, and software activation.

1. Hardware components

To begin the process, you will need several specific components: 

• Front and rear RDC sensors: These radio sensors are installed inside the tire on the wheel rim, replacing the standard valve stems.

• RDC control unit: This module processes the data from the wheel sensors. For many newer bikes, a wiring harness may already be in place with a dummy plug, making installation more straightforward. For other models, you will need to install wiring to connect the control unit to the bike's electrical system.

• Associated hardware: This includes specialized valve nuts, seals, and other small parts for installation. 

2. Hardware installation

The physical installation involves several technical tasks: 

• Wheel and tire removal: Both the front and rear wheels must be removed from the motorcycle to access the valve stem area.

• Sensor mounting: The tires are demounted, and the new RDC sensors are carefully installed on the inside of the rim, replacing the existing valve stems. It is crucial to have this work performed by a tire specialist to avoid damaging the new sensors or wheels.

• Tire re-mounting and balancing: The tires are re-mounted, inflated to the correct pressure, and balanced, a standard step in any tire-fitting process.

• RDC control unit installation: The new control unit is installed, often under the seat, and connected to the main wiring harness. 

3. Software coding and activation

After the hardware is in place, the bike's electronics must be configured to recognize and use the new sensors. 

• Connect to diagnostic tools: The BMW Motorrad technician connects the bike to a diagnostic tool like a GS-911 or the official BMW Motorrad Diagnostic System.

• Register the new system: The technician performs the necessary coding to activate the RDC feature in the bike's ECU. This process effectively tells the bike that it now has an RDC system installed.

• Pair the sensors: The individual RDC sensor IDs for the front and rear wheels are paired with the bike's computer. This is often done by putting the system in "learn" mode and then "waking up" each sensor, which can be accomplished by using a special tool or by temporarily and rapidly releasing air from the tire.

• Test ride: A test ride is performed to ensure the sensors are functioning and communicating with the bike's display. 

Key considerations

• Professional installation: Due to the need for specialized tire tools and electronic programming, this is not a straightforward DIY job. Professional installation ensures proper calibration and function.

• Part compatibility: RDC sensor technology has evolved. It is important to ensure the parts (sensors and control unit) are compatible with your specific motorcycle model year.

• Cost: The retrofit cost includes the parts (sensors, control unit), the labor for installation and programming, and the potential cost of tire service.